1. Field of the Invention
The invention relates to a mechanical stretching device for a multifunctional convertible sofa, which is mainly applied to a convertible sofa, and is a furniture component.
2. Related Art
A current mechanical stretching device for a convertible sofa has three major defects: 1. the length increased by unfolding is not consistent with the length reduced by folding, so that an iron frame cannot be unfolded or a soft pad in the front of a seat subsides to affect appearance; 2. a back is loose by about 40 mm, backs of a two-seat or three-seat functional sofa are not aligned, and a stagger distance is very long especially after stretching which affects the grade or style of the sofa; and 3. after a load is placed, the product subsides by about 40 mm, and the sofa is a certain distance away from the ground.